Lab 1: Neuroanatomy: The Divisions, the Neuron & the Cerebrum

afferent divison

receives sensory input from sensory receptors located all over the body & sends information about internal bodily states and the external environment for the CNS to process

efferent divison

outputs the processed motor commands from the CNS to effector organs of the body

somatic nervous system (SNS)

the part of the peripheral nervous system that controls voluntary movement of skeletal muscles (conscious)

autonomic nervous system (ANS)

not under conscious control & sends out commands to smooth muscles, cardiac muscles and all other visceral effector organs

Sympathetic Nervous System (SNS)

"fight or flight" response of ANS

Parasympathetic nervous system (PNS)

"rest and digest" functions of ANS

neuron (function)

electrically excitable cells that transmit signals throughout the body

neuron (picture)

common features of neuron

1) dendrites

2) cell body or soma

3) axon

dendrites (function)

branches around the cell body responsible for collecting information from neighbor neurons (through neurotransmitters) and pass this formation to the cell body or along the cell body and its axon to an effector organ or muscle

dendrites (picture)

cell body (soma) (function)

command center or the neuron

cell body (soma) (picture)

axon (function)

- branches off cell body into a relatively thick filament

- generates action potential

axon (picture)

C

axon hillock (function)

region in which the axon originates

axon hillock (picture)

initial segment (function)

- the starting point of action potentials

- located after axon hillock

initial segment (picture)

myelin sheath (function)

coating that insulates neuron & speeds transmission

myelin sheath (picture)

cerebrum (brain cortex)

composed of the right and left hemispheres

cerebrum (brain cortex) (picture)

grey matter

cell bodies

grey matter (picture)

white matter

myelinated axons

white matter (picture)

gyri (function)

bulges of the brain cortex

sulci (function)

shallow groves that border and separate gyri

right side of brain controls

left side of the body

left side of brain controls

right side of the body

Lobes of the brain

frontal lobe, parietal lobe, occipital lobe, temporal lobe, insula

frontal lobe (function)

thinking, speaking, memory, movement

frontal lobe (picture)

parietal lobe (function)

language, touch, taste, smell

parietal lobe (picture)

occipital lobe (function)

vision, color, letters, left/right

occipital lobe (picture)

Cerebellum (function)

Balance, coordination

Cerebellum (picture)

brain stem (function)

breathing, heart rate, temperature, blood pressure

brain stem (picture)

temporal lobe (function)

hearing, learning, feelings, fear

temporal lobe (picture)

insular lobe (function)

- found deeper in the temporal lobe

- balance, motor control, autonomic control, taste

insular lobe (picture)

longitudinal fissure (function)

deep groove that runs sagittally over the cerebrum & separates the right from the left hemisphere

longitudinal fissure (picture)

central sulcus (function)

deep groove that runs inferiorly in between the frontal & parietal lobe

central sulcus (picture)

parieto-occipital sulcus (function)

located medially, runs coronally at the back of the cerebrum separating the parietal & occipital lobes

parieto-occipital sulcus (picture)

lateral sulcus or fissure (function)

bordered above & across the temporal lobe, separating it from the frontal & parietal lobes

lateral sulcus or fissure (picture)

transverse fissure (function)

deep fissure that cuts between the cerebrum & the cerebellum

transverse fissure (picture)

corpus callosum (function)

a thick & curved bundle of white nerve tracts connecting the left & right hemisphere

corpus callosum (picture)

precentral gyrus (function)

located anterior to the central sulcus, this region houses the primary motor cortex and is involved in the production of voluntary movements

precentral gyrus (picture)

postcentral gyrus (function)

located posterior to the central sulcus, this region house the primary somatosensory cortex and is involed in conscious processing of sensations

postcentral gyrus (picture)

cranial meninges (outer to inner)

1) dura mater

2) arachnoid mater

3) pia mater

cranial meninges (outer to inner) (picture)

dura mater (function)

- outermost layer, extremely thick & hard, with a periosteal layer in the outside that fuses with cranial bones & a thinner meningeal layer in the inside that lies on top of the arachnoid mater

- has extensions that fold into the brain to divide important regions of the brain and promote stability among them

- a subdural space will run in between the dura & arachnoid mater

dura mater (picture)

1

arachnoid mater (function)

weblike middle layer that has multiple stringy filaments that provide a smooth cushion over the brain & connects to the pia mater

arachnoid mater (picture)

2

pia mater (function)

- very thin film which sits tightly on top of the brain

- allows for exchange of gasses & nutrients

pia mater (function) (picture)

3

cerebral spinal fluid is located between which two meninges?

arachnoid mater & pia mater